Severe aortic stenosis by Doppler criteria was inconsistent with CT-derived aortic valve area (>1 cm2) in up to 23% of patients, primarily due to high left ventricular outflow tract flow rates.
Observational (n=450)
What is the prevalence and mechanism of inconsistency in aortic stenosis severity grading between CT and echocardiography in patients undergoing TAVI assessment?
Severe aortic stenosis by Doppler criteria may be exaggerated due to high LVOT flow rates, and CT evaluation can help clarify severity in up to a quarter of patients.
Objectives The aims of this study were to evaluate the inconsistency of aortic stenosis (AS) severity between CT aortic valve area (CT-AVA) and echocardiographic Doppler parameters, and to investigate potential underlying mechanisms using computational fluid dynamics (CFD). Methods A total of 450 consecutive eligible patients undergoing transcatheter AV implantation assessment underwent CT cardiac angiography (CTCA) following echocardiography. CT-AVA derived by direct planimetry and echocardiographic parameters were used to assess severity. CFD simulation was performed in 46 CTCA cases to evaluate velocity profiles. Results A CT-AVA>1 cm 2 was present in 23% of patients with echocardiographic peak velocity≥4 m/s (r=−0.33) and in 15% patients with mean Doppler gradient≥40 mm Hg (r=−0.39). Patients with inconsistent severity grading between CT and echocardiography had higher stroke volume index (43 vs 38 mL/m 2 , p1 cm 2 in up to a quarter of patients. CFD demonstrates that haemodynamic severity may be exaggerated on Doppler analysis due to high LVOT flow rates, with or without skewed velocity profiles, across the valve orifice. These factors should be considered before making a firm diagnosis of severe AS and evaluation with CT can be helpful.
Mittal et al. (Mon,) conducted a observational in Aortic stenosis (n=450). CT cardiac angiography and computational fluid dynamics vs. Echocardiography was evaluated on Inconsistency of aortic stenosis severity between CT aortic valve area and echocardiographic Doppler parameters. Severe aortic stenosis by Doppler criteria was inconsistent with CT-derived aortic valve area (>1 cm2) in up to 23% of patients, primarily due to high left ventricular outflow tract flow rates.